AI coding tools added $942M to hospital bills, BCBS says

Hospitals' AI billing tools added an estimated $942 million to Blue Cross Blue Shield plan costs across 2024 and 2025 versus 2023 levels, according to an analysis by the Blue Cross Blue Shield Association that The New York Times reported this week. Hospitals were paid, on average, nearly $12,000 more per case because of the way the tools are sending codes, with roughly $653 million of the increase tied to secondary diagnoses that pushed claims into higher-paying categories.

The share of inpatient stays billed as "medically complex" rose from 37% at the start of 2023 to 40% by the end of 2025. Billing codes for secondary conditions like partial intestinal blockages and elevated acid climbed 55% and 33% respectively over that window. More than 60% of hospital systems have adopted AI coding tools that document visits and read lab reports and doctors' notes, and the BCBSA analysis argues the coding is drifting away from the care actually delivered.

"For example, we're seeing significantly more anemia diagnoses at these hospitals without a corresponding increase in transfusions," the BCBSA writes. "The disconnect between diagnoses and treatment suggests that AI is identifying more billable conditions, not sicker patients."

Hospitals reject that framing. The American Hospital Association said in August that rising coding intensity can reflect patients becoming older and sicker, along with more accurate documentation of pre-existing conditions. The Times notes that insurers are also deploying AI on the other side of the same claims, to review and deny them, a dynamic several of the health-policy analysts we follow flagged the day the story ran.

Battles between hospitals and insurers over what a case is worth are not new. The BCBSA's framing is that AI is now the accelerant.